<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      // var num = 10
      // var num1 = 30
      // function fun() {
      //   console.log(num)
      //   var num = 20
      //   console.log(num)
      //   function fun1() {
      //     var num = 40
      //     console.log(num)
      //     console.log(num1)
      //   }
      //   var num1 = 80
      //   fun1()
      // }
      // console.log(num)
      // fun()
      var num
      var num1
      function fun() {
        var num
        console.log(num)
        num = 20
        console.log(num)
        function fun1() {
          var num = 40
          console.log(num)
          console.log(num1)
        }
        var num1 = 80
        fun1()
      }
      num = 10
      num1 = 30
      console.log(num)
      fun()
    </script>
  </body>
</html>
